This invention relates to a hair shampoo composition which deposits a hair conditioning ingredient on the hair at the same time that oil and dirt are washed from the hair. In particular, it relates to a shampoo composition containing amine functional polydiorganosiloxane as a hair conditioning component.
Detersive surfactants used for washing hair do not distinguish between oil which is dirt or which exceeds requirements and oil which is essential for the proper care and appearance of hair. Unless the hair is washed with an extremely weak shampoo or very infrequently, it is desirable to return some oil or other material to the hair to "condition" it. For example, the use of after-shampoo conditioning products in order to return materials to hair which improve its characteristics and appearance is well known. However, it has been recognized for a long time that a shampoo that could simultaneously clean and deposit a conditioning substance on hair would be more efficient and convenient.
Unfortunately, conditioning substances which may be beneficially applied to hair in after-shampoo products are often ineffective or only marginally effective when used in shampoo compositions. The nature of the conditioning substance and the composition of the shampoo from which it is intended to be deposited are factors which affect the extent of conditioning benefits actually realized. Moreover, a conditioning substance when added to a shampoo formulation can cause problems such as reduced foaming, cloudiness, and instability which results in precipitation or separation of components.
Accordingly, it is a purpose of the present invention to provide improved conditioning shampoo compositions that simultaneously cleanse the hair and deposit a conditioning substance on the hair. Further it is a purpose of the present invention to provide conditioning shampoo compositions that effectively condition hair and at the same time provide the hair with a clean, non-greasy feeling. In addition, it is a purpose of the present invention to provide shampoo compositions in which the components form a stable, non-separating mixture.
It is taught in U.S. Pat. No. 4,342,742 to Sebag et al. that surface active polysiloxanes, represented by the formula ##STR1## where x denotes an integer from 3 to 10 and A denotes a hydrophilic unit, are useful in cosmetic and pharmaceutical compositions, especially compositions for hair. Sebag et al. teach that the hydrophilic unit A can be cationic, zwitterionic, anionic or nonionic and may comprise amine, amine oxide, ammonium, ammonioalkylcarboxylate, ammonioalkylsulphate, amide, sulphonamide, ether, thioether, sulphoxide, hydroxyl, ester or acid groups. More specifically Sebag et al. teach a shampoo composition containing triethanolamine lauryl sulphate, lauryl diethanolamide, sufficient HCl to adjust the pH to 7.5, water, and a polysiloxane of the above formula where A denotes the --COOH group.
It is known from German Patent Application No. 2,912,485 to use certain quaternary nitrogen derivatives of polysiloxanes in hair shampoos to improve the wet combing, softness and body of the washed air. A shampoo composition is described containing 30% sodium lauryl ether sulfate (27/28% active), 2% NaCl, 2% coconut fatty acid diethanolamide, 5% of a 50% aqueous solution of silicone of the formula EQU R--Si(CH.sub.3).sub.2 O--[Si(CH.sub.3).sub.2 O].sub.17 --Si(CH.sub.3).sub.2 --R
where R is --(CH.sub.2).sub.10 CONH(CH.sub.2).sub.3 N.sup.+ (CH.sub.3).sub.2 CH.sub.2 C.sub.6 H.sub.5.Cl.sup.-, 1% Zn pyridine-thione, 1% protein hydrolyzate, 1% perfume and 58% water. In addition, German Patent Application 2,912,484 teaches that certain polysiloxane polymers with side chains containing quaternary nitrogen groups are useful as components of hair washing or treating compositions. The quaternary nitrogen groups described as useful on the siloxane are the same as described in German Patent Application 2,912,485, but the groups are attached along the siloxane polymer chain instead of only at the ends of the siloxane chain. Useful siloxanes are reported to contain from 0-300 nonfunctional siloxane units and 1-75 quaternary nitrogen functional siloxane units.
Similarly, it is taught in Japanese Kokai Patent No. Sho 55[1980]-66506 that certain siloxane polymers with quaternary nitrogen contents of 0.7 to 5.5 weight percent can be employed as conditioning components in shampoo compositions. The quaternary nitrogen containing siloxanes are reported to form complex salts with anionic surfactants. These complex salts, however, are said to be soluble in a transparent state in aqueous solutions in the presence of the anionic surfactants.
In U.S. Pat. No. 4,185,087, Morlino teaches that certain quaternary nitrogen derivatives of trialkylamino hydroxy organosilicon polymers are useful in hair conditioning compositions and shampoos. The preferred siloxane polymers described by Morlino have the formula ##STR2## wherein x is 2 to 8, y is 20 to 50, and R' is a divalent alkylene having from 1 to 8 carbon atoms.
The quaternary nitrogen containing siloxanes described in the above references are generally water soluble or compatible and are reported to be easily formulated into clear shampoo compositions. While such shampoo compositions may provide some conditioning of hair as it is cleaned, there is still a need for further improvement. Moreover, the quaternary nitrogen containing siloxanes are difficult and complicated materials to prepare so that it would be advantageous if simpler, less costly siloxane polymers could be used in hair shampoo compositions.
Certain amine functional siloxanes such as amodimethicone are known to provide excellent hair conditioning when applied to hair from an aqueous emulsion after the hair has been shampooed. However, formulation difficulties are encountered when emulsions of amine functional siloxanes are added to shampoo compositions. The siloxane emulsion causes cloudiness and may be so unstable in the shampoo composition that phase separation occurs. Although the cloudiness may be disguised by using a pearling agent such as glycol stearate, shampoo compositions containing emulsions of amine functional siloxanes have not been completely satisfactory. However, the Encyclopedia of Shampoo Ingredients by Anthony L. L. Hunting, 1983, teaches that amodimethicone has been used as a component of a peallized (i.e., nonclear) shampoo composition. Amodimethicone is an amine substituted siloxane polymer containing reactive silanol (SiOH) functionality that is stabilized in an aqueous emulsion by a cationic and a nonionic surfactant. The siloxane polymer is represented by the formula ##STR3## where x and y are numbers depending on the molecular weight of the polymer. When the emulsion is broken, the siloxane polymer is no longer stabilized and may crosslink and cure by condensation of the silanol groups.
United States application for patent, Ser. No. 595,224, filing date Mar. 30, 1984, and assigned to the same assignee as this present application, teaches that an aqueous emulsion containing an aminoalkyl substituted polydimethylsiloxane is useful as an after-shampoo hair conditioner because it facilitates combing and imparts a smooth feel to hair.
United States application for patent, Ser. No. 632,357, filing date July 19, 1984, and assigned to a subsidiary of the assignee of this present application, teaches a shampoo composition containing as essential components (1) a silane or a polydiorganosiloxane having a quaternary ammonium substituted group attached to silicon, (2) a polydiorganosiloxane having silicon-bonded substituents which are amine-substituted hydrocarbon groups, (3) one or more surfactants, and (4) water. An exemplary shampoo composition is shown containing linoleic diethanolamide and pearling agent as additional nonessential components. The amine functional siloxane (component 2) is added to the shampoo in the form of an aqueous emulsion. These shampoo compositions are reported to provide improved fullness and body to hair.
United States application for patent, Ser. No. 542,639, filing date Oct. 17, 1983, and assigned to the same assignee as this present application, teaches a method of preparing clear microemulsions of amine functional polyorganosiloxanes. It is further taught that transparent microemulsions of amine functional siloxanes can be mixed with a shampoo base of sodium lauryl ether sulfate and water to produce a stable, transparent composition.